Image of car keys and cannabis

It’s no secret that driving while drunk is extremely dangerous. The National Highway Traffic Safety Administration says that one person was killed in a drunk driving crash every 45 minutes in the U.S. in 2020 alone.

However, many people are either unaware of or underestimate the dangers of driving while high. Even though marijuana is illegal for recreational possession and use in South Carolina, some drivers get behind the wheel of their vehicles while impaired by its psychoactive ingredient THC.

In addition, many users think its effects are safer than alcohol when it comes to driving ability. That’s not the case. Here’s what the science says.

There’s a Strong Relationship Between High THC Levels and Reduced Driving Ability

The National Institute on Drug Abuse says that marijuana is the illicit drug most frequently found in the blood of drivers who have been involved in all types of vehicle crashes, including fatal accidents.

In addition, a European Union study found that drivers who had detectable levels of THC in their blood doubled their risk of causing fatal crashes compared to drivers who weren’t impaired by drugs or alcohol.

The Centers for Disease Control and Prevention says both marijuana usage and THC impairment can affect driving ability by:

  • Delaying response times
  • Impairing judgment and decision-making abilities
  • Causing or increasing anxiety
  • Distorting memory making it difficult to recall nearby vehicle positions
  • Impairing coordination making the actual task of driving more difficult

The Number of THC-Related Crashes Is Increasing

The New York Times says that from 2000 to 2018, the percentage of motor vehicle fatalities involving cannabis more than doubled from 9% to 22%. Meanwhile, the number of fatal alcohol-related crashes remained roughly the same during the same time period.

Even in states where recreational or medical marijuana usage is legal, drivers can be held liable if they cause crashes that injure or kill others while under its influence.

Drivers High on Marijuana Can Be Charged with DUI

South Carolina Code § 56-5-2930 says:

 “It is unlawful for a person to drive a motor vehicle within this State while under the influence of alcohol to the extent that the person’s faculties to drive a motor vehicle are materially and appreciably impaired, under the influence of any other drug or a combination of other drugs or substances which cause impairment to the extent that the person’s faculties to drive a motor vehicle are materially and appreciably impaired, or under the combined influence of alcohol and any other drug or drugs or substances which cause impairment to the extent that the person’s faculties to drive a motor vehicle are materially and appreciably impaired.”

In other words, South Carolina law says that drivers can be charged with DUI if they’re under the influence of marijuana or other drugs in addition to alcohol.

After a crash or during a traffic stop, police may initiate a marijuana-related DUI arrest if they notice the following:

  • Marijuana odor emanating from the vehicle
  • Seeing marijuana in the vehicle
  • Seeing marijuana-related paraphernalia in the vehicle
  • Hearing an admission of smoking marijuana from the driver of the vehicle

Proving Marijuana Impairment Can Be Difficult After a Crash

Unlike alcohol impairment, which can be quickly proven after a crash via a Breathalyzer test or blood test, proving marijuana impairment is much more difficult. While the psychoactive effects of marijuana may last for only a few hours, THC can remain in a person’s blood for weeks.

That means a person who tests positive for marijuana usage may not have been under the influence of it at the time of their crash. Because proof of THC blood levels isn’t definitive proof of impairment at the time of a crash or traffic stop, police often rely on the following in addition to positive THC screenings:

  • Failed field sobriety tests
  • Erratic driving behavior

Our Car Accident Lawyers Hold Stoned Drivers Liable When They Cause Crashes

At Joye Law Firm, we have no sympathy or tolerance for drunk drivers when they cause crashes. The same is true for people who get behind the wheel while impaired by illegal drugs, including marijuana.

Driving is a highly complex and difficult task that many people take for granted. Doing it while under the influence of substances that can affect and impair both the mental and physical skills needed to safely control a motor vehicle is both reckless and negligent.

If you or someone you love was hurt by an intoxicated or impaired driver, our South Carolina car accident attorneys want to help. Contact us today for a free consultation.

About the Author

Mark Joye is the Head of the Litigation Department at the Joye Law Firm. A Board-Certified Trial Advocate with nearly 30 years of litigation experience, he currently serves on the Board of Governors for the American Association for Justice and is a past president of the South Carolina Association for Justice. In a recent trial, Joye headed a trial team that secured $17 million for a family killed in a tractor-trailer accident.

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